<!DOCTYPE html>
<html lang="zh">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>登录页</title>
</head>
<script>

</script>
<body>
    <form action="/doLogin" method="post">
        用户名：<input name="username" type="text" required 
        placeholder="请输入用户名" oninvalid="setCustomValidity('用户名不能为空')" oninput="setCustomValidity('')"></input>
        <br>
        密码：<input name="password" type="password"  
        placeholder="请输入密码" oninvalid="setCustomValidity('密码不能为空')"></input>
        <br>
        <button type="submit">登录</submit>
    </form>
</body>
</html>